An item designed for the purpose of injecting a carefully controlled amount of foam liquid into a horizontal fire main or fire hose line depending upon the flow of water through the main or line. it consists of a positive displacement rotary foam liquid pump driven by a positive displacement rotary water motor through a solid type coupling. The pump suction is connected to a source of foam liquid and the discharge is connected to the downstream side of the water motor. For tank type proportioners, see PROPORTIONER, FIRE EXTINGUISHING FOAM. Excludes GENERATOR, FOAM, PUMP.